linux-stable.git/net/dsa, branch v5.17.2

net: dsa: fix panic on shutdown if multi-chip tree failed to probe

2022-04-08T11:58:22+00:00

[ Upstream commit 8fd36358ce82382519b50b05f437493e1e00c4a9 ]

DSA probing is atypical because a tree of devices must probe all at
once, so out of N switches which call dsa_tree_setup_routing_table()
during probe, for (N - 1) of them, "complete" will return false and they
will exit probing early. The Nth switch will set up the whole tree on
their behalf.

The implication is that for (N - 1) switches, the driver binds to the
device successfully, without doing anything. When the driver is bound,
the ->shutdown() method may run. But if the Nth switch has failed to
initialize the tree, there is nothing to do for the (N - 1) driver
instances, since the slave devices have not been created, etc. Moreover,
dsa_switch_shutdown() expects that the calling @ds has been in fact
initialized, so it jumps at dereferencing the various data structures,
which is incorrect.

Avoid the ensuing NULL pointer dereferences by simply checking whether
the Nth switch has previously set "ds->setup = true" for the switch
which is currently shutting down. The entire setup is serialized under
dsa2_mutex which we already hold.

Fixes: 0650bf52b31f ("net: dsa: be compatible with masters which unregister on shutdown")
Signed-off-by: Vladimir Oltean 
Link: https://lore.kernel.org/r/20220318195443.275026-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net: dsa: Avoid cross-chip syncing of VLAN filtering

2022-04-08T11:57:58+00:00

[ Upstream commit 108dc8741c203e9d6ce4e973367f1bac20c7192b ]

Changes to VLAN filtering are not applicable to cross-chip
notifications.

On a system like this:

.-----.   .-----.   .-----.
| sw1 +---+ sw2 +---+ sw3 |
'-1-2-'   '-1-2-'   '-1-2-'

Before this change, upon sw1p1 leaving a bridge, a call to
dsa_port_vlan_filtering would also be made to sw2p1 and sw3p1.

In this scenario:

.---------.   .-----.   .-----.
|   sw1   +---+ sw2 +---+ sw3 |
'-1-2-3-4-'   '-1-2-'   '-1-2-'

When sw1p4 would leave a bridge, dsa_port_vlan_filtering would be
called for sw2 and sw3 with a non-existing port - leading to array
out-of-bounds accesses and crashes on mv88e6xxx.

Fixes: d371b7c92d19 ("net: dsa: Unset vlan_filtering when ports leave the bridge")
Signed-off-by: Tobias Waldekranz 
Reviewed-by: Vladimir Oltean 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: dsa: Move VLAN filtering syncing out of dsa_switch_bridge_leave

2022-04-08T11:57:58+00:00

[ Upstream commit 381a730182f1d174e1950cd4e63e885b1c302051 ]

Most of dsa_switch_bridge_leave was, in fact, dealing with the syncing
of VLAN filtering for switches on which that is a global
setting. Separate the two phases to prepare for the cross-chip related
bugfix in the following commit.

Signed-off-by: Tobias Waldekranz 
Reviewed-by: Vladimir Oltean 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: dsa: Add missing of_node_put() in dsa_port_parse_of

2022-03-17T12:13:27+00:00

The device_node pointer is returned by of_parse_phandle()  with refcount
incremented. We should use of_node_put() on it when done.

Fixes: 6d4e5c570c2d ("net: dsa: get port type at parse time")
Signed-off-by: Miaoqian Lin 
Link: https://lore.kernel.org/r/20220316082602.10785-1-linmq006@gmail.com
Signed-off-by: Paolo Abeni

net: dsa: unlock the rtnl_mutex when dsa_master_setup() fails

2022-03-06T10:55:54+00:00

After the blamed commit, dsa_tree_setup_master() may exit without
calling rtnl_unlock(), fix that.

Fixes: c146f9bc195a ("net: dsa: hold rtnl_mutex when calling dsa_master_{setup,teardown}")
Signed-off-by: Vladimir Oltean 
Signed-off-by: David S. Miller

net: dsa: make dsa_tree_change_tag_proto actually unwind the tag proto change

2022-03-03T16:39:12+00:00

The blamed commit said one thing but did another. It explains that we
should restore the "return err" to the original "goto out_unwind_tagger",
but instead it replaced it with "goto out_unlock".

When DSA_NOTIFIER_TAG_PROTO fails after the first switch of a
multi-switch tree, the switches would end up not using the same tagging
protocol.

Fixes: 0b0e2ff10356 ("net: dsa: restore error path of dsa_tree_change_tag_proto")
Signed-off-by: Vladimir Oltean 
Link: https://lore.kernel.org/r/20220303154249.1854436-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski

net: dsa: restore error path of dsa_tree_change_tag_proto

2022-03-02T02:26:21+00:00

When the DSA_NOTIFIER_TAG_PROTO returns an error, the user space process
which initiated the protocol change exits the kernel processing while
still holding the rtnl_mutex. So any other process attempting to lock
the rtnl_mutex would deadlock after such event.

The error handling of DSA_NOTIFIER_TAG_PROTO was inadvertently changed
by the blamed commit, introducing this regression. We must still call
rtnl_unlock(), and we must still call DSA_NOTIFIER_TAG_PROTO for the old
protocol. The latter is due to the limiting design of notifier chains
for cross-chip operations, which don't have a built-in error recovery
mechanism - we should look into using notifier_call_chain_robust for that.

Fixes: dc452a471dba ("net: dsa: introduce tagger-owned storage for private and shared data")
Signed-off-by: Vladimir Oltean 
Link: https://lore.kernel.org/r/20220228141715.146485-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski

net: dsa: fix panic when removing unoffloaded port from bridge

2022-02-23T01:03:02+00:00

If a bridged port is not offloaded to the hardware - either because the
underlying driver does not implement the port_bridge_{join,leave} ops,
or because the operation failed - then its dp->bridge pointer will be
NULL when dsa_port_bridge_leave() is called. Avoid dereferncing NULL.

This fixes the following splat when removing a port from a bridge:

 Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000
 Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP
 CPU: 3 PID: 1119 Comm: brctl Tainted: G           O      5.17.0-rc4-rt4 #1
 Call trace:
  dsa_port_bridge_leave+0x8c/0x1e4
  dsa_slave_changeupper+0x40/0x170
  dsa_slave_netdevice_event+0x494/0x4d4
  notifier_call_chain+0x80/0xe0
  raw_notifier_call_chain+0x1c/0x24
  call_netdevice_notifiers_info+0x5c/0xac
  __netdev_upper_dev_unlink+0xa4/0x200
  netdev_upper_dev_unlink+0x38/0x60
  del_nbp+0x1b0/0x300
  br_del_if+0x38/0x114
  add_del_if+0x60/0xa0
  br_ioctl_stub+0x128/0x2dc
  br_ioctl_call+0x68/0xb0
  dev_ifsioc+0x390/0x554
  dev_ioctl+0x128/0x400
  sock_do_ioctl+0xb4/0xf4
  sock_ioctl+0x12c/0x4e0
  __arm64_sys_ioctl+0xa8/0xf0
  invoke_syscall+0x4c/0x110
  el0_svc_common.constprop.0+0x48/0xf0
  do_el0_svc+0x28/0x84
  el0_svc+0x1c/0x50
  el0t_64_sync_handler+0xa8/0xb0
  el0t_64_sync+0x17c/0x180
 Code: f9402f00 f0002261 f9401302 913cc021 (a9401404)
 ---[ end trace 0000000000000000 ]---

Fixes: d3eed0e57d5d ("net: dsa: keep the bridge_dev and bridge_num as part of the same structure")
Signed-off-by: Alvin Šipraga 
Reviewed-by: Vladimir Oltean 
Reviewed-by: Florian Fainelli 
Link: https://lore.kernel.org/r/20220221203539.310690-1-alvin@pqrs.dk
Signed-off-by: Jakub Kicinski

net: dsa: avoid call to __dev_set_promiscuity() while rtnl_mutex isn't held

2022-02-19T21:18:33+00:00

If the DSA master doesn't support IFF_UNICAST_FLT, then the following
call path is possible:

dsa_slave_switchdev_event_work
-> dsa_port_host_fdb_add
   -> dev_uc_add
      -> __dev_set_rx_mode
         -> __dev_set_promiscuity

Since the blamed commit, dsa_slave_switchdev_event_work() no longer
holds rtnl_lock(), which triggers the ASSERT_RTNL() from
__dev_set_promiscuity().

Taking rtnl_lock() around dev_uc_add() is impossible, because all the
code paths that call dsa_flush_workqueue() do so from contexts where the
rtnl_mutex is already held - so this would lead to an instant deadlock.

dev_uc_add() in itself doesn't require the rtnl_mutex for protection.
There is this comment in __dev_set_rx_mode() which assumes so:

		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */

but it is from commit 4417da668c00 ("[NET]: dev: secondary unicast
address support") dated June 2007, and in the meantime, commit
f1f28aa3510d ("netdev: Add addr_list_lock to struct net_device."), dated
July 2008, has added &dev->addr_list_lock to protect this instead of the
global rtnl_mutex.

Nonetheless, __dev_set_promiscuity() does assume rtnl_mutex protection,
but it is the uncommon path of what we typically expect dev_uc_add()
to do. So since only the uncommon path requires rtnl_lock(), just check
ahead of time whether dev_uc_add() would result into a call to
__dev_set_promiscuity(), and handle that condition separately.

DSA already configures the master interface to be promiscuous if the
tagger requires this. We can extend this to also cover the case where
the master doesn't handle dev_uc_add() (doesn't support IFF_UNICAST_FLT),
and on the premise that we'd end up making it promiscuous during
operation anyway, either if a DSA slave has a non-inherited MAC address,
or if the bridge notifies local FDB entries for its own MAC address, the
address of a station learned on a foreign port, etc.

Fixes: 0faf890fc519 ("net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work")
Reported-by: Oleksij Rempel 
Signed-off-by: Vladimir Oltean 
Signed-off-by: David S. Miller

net: dsa: lan9303: handle hwaccel VLAN tags

2022-02-17T17:32:06+00:00

Check for a hwaccel VLAN tag on rx and use it if present.  Otherwise,
use __skb_vlan_pop() like the other tag parsers do.  This fixes the case
where the VLAN tag has already been consumed by the master.

Fixes: a1292595e006 ("net: dsa: add new DSA switch driver for the SMSC-LAN9303")
Signed-off-by: Mans Rullgard 
Reviewed-by: Vladimir Oltean 
Link: https://lore.kernel.org/r/20220216124634.23123-1-mans@mansr.com
Signed-off-by: Jakub Kicinski